1. Field of the Invention
The present invention relates generally to a photographing system, and more particularly to an improvement in a photographing system in which a plurality of photographing methods are prepared according to a difference in a photographing object.
2. Description of the Related Art
In the field of biological chemistry and molecular biology, a fluorescence detecting system using a fluorescent dye as a labeling material is hitherto known. According to this system, the evaluations or the like of the arrangement of a gene, the expression level of a gene, the path and state of the metabolism, absorption, and excretion of an applied material in a laboratory mouse, and the separation, identification, molecular weight, and characteristics of protein can be performed, by reading out image information related to a sample distributing specific organism-originated materials labeled with a fluorescent dye.
For example, by utilizing the electrophoresis that causes a living cell in suspension or a biological compound (protein, etc.) in a solution to move to a positive or negative electrode through an electric field by the electric charge, a plurality of deoxyribonucleic acid (DNA) fragments are electrophoresed on a gel support body, after a fluorescent dye has been added into a solution containing the plurality to of DNA fragments. Alternatively, a plurality of DNA fragments are electrophoresed on a gel support body contained with a fluorescent dye, or, after a plurality of DNA fragments have been electrophoresed on a gel support body, this gel support body is immersed into a solution containing a fluorescent dye. In this way, a gel support body (sample) distributing specific DNA fragments (organism-originated materials) labeled with fluorescence is obtained. Within a black box shielded from external light, the obtained gel support body placed on a suitable sample tray is irradiated with excitation light for exciting the fluorescent dye employed as a labeling material. The fluorescence emitted from the gel support body is photoelectrically read out. In this way, image information representing a distribution of DNA fragments labeled with fluorescence is acquired, and based on the acquired image information, a visual image is displayed on a display section such as a CRT display, whereby the evaluation of the molecular weight of the DNA fragment and the like can be performed.
On the other hand, in the same field, a chemiluminescence method of photographing an image of chemiluminescence by employing photoelectric reading means such as a charged-coupled device (CCD) is known as a method of detecting a nucleic acid and protein in a membrane filter or the like after blotching. As an apparatus for photographing such an image of chemiluminescence, a photographing apparatus is known in which, as with the aforementioned fluorescence detecting apparatus, a membrane filter or the like is placed on a suitable sample tray and housed within a block box shielded from external light. Within this black box, chemiluminescence emitted from the membrane filter or the like is photoelectrically read out by photoelectric reading means through a lens, and in this way, image information representing a distribution of specific protein or the like reacting to a predetermined luminescent chemical material is acquired.
Here, the aforementioned photographing apparatus with the object of detecting chemiluminescence can also be used as a photographing apparatus for the aforementioned fluorescence detecting system, by further providing an exciting-light source which emits exciting light capable of exciting a fluorescent dye and an exciting-light cut filter for transmitting only fluorescence to the photoelectric reading means and preventing passage of exciting light. Therefore, a photographing apparatus adding the function of detecting fluorescence to the photographing apparatus for chemiluminescence detection has been developed.
That is, in the case of performing photographing for chemiluminescence detection, exciting light is prevented from being emitted. Also, the exciting-light cut filter is removed from the optical path of chemiluminescence, and chemiluminescence emitted from a sample is detected by the photoelectric reading means. On the other hand, in the case of performing photographing for fluorescence detection, a sample is illuminated with exciting light, the exciting-light cut filter is disposed in the optical path of fluorescent emitted from the sample, and the light source and the exciting-light cut filter are switched separately or integrally such that fluorescence alone is detected by the photoelectric reading means. Furthermore, in the case where there is a great difference in intensity between fluorescence and chemiluminescence, the quantity of light to be incident on the photoelectric reading means is adjusted by providing a variable diaphragm.
Furthermore, the aforementioned photographing apparatus can also be used as a digitizer, in which a translucent manuscript (film, etc.) or a reflecting manuscript (a photograph, etc.) is irradiated and the transmitted image or the reflected image is photoelectrically read out by photoelectric reading means through a lens, thereby obtaining a digital image. In this case, the light to be emitted from the exciting light source employs white light, not the exciting light in a band that can excite fluorescence. In this way, the quantity of light to be incident on the photoelectric reading means is limited.
Also, in the photographing apparatus thus rendering switching of photographing methods possible in accordance with a photographing object, an apparatus capable of photographing an image appropriate to the size of a sample by varying a viewing angle of view that is incident on photoelectric reading means through a lens is known. More specifically, a plurality of disposing sections each having a different distance from the lens are formed as sample-tray disposing sections on which a sample tray is disposed. A sample tray can be disposed selectively on one sample-tray disposing section of the plurality of sample-tray disposing sections. The lens is moved in the optical axis direction in accordance with the selected sample-tray disposing section, whereby focusing on the light-receiving surface of the photoelectric reading means is rendered possible.
Incidentally, it is common practice for the image signal acquired by the aforementioned photographing apparatus to be given various kinds of image processing by an image processing computer (including a personal computer (PC)) and is employed in quantitative analysis or the like. Usually, the photographing apparatus and the image processing computer constitute a photographing system.
As an example of the image processing to be performed by the image processing computer, there are various kinds of correction processing. For instance, the shading correction of correcting peripheral extinction due to the lens of the photographing apparatus corresponds to this correction processing. In this shading correction processing, the processing condition varies according to the aforementioned photographing method including selection of the sample-tray disposing section.
More specifically, when the photographing method detects chemiluminescence, the processing condition is, for example, that lens brightness data is previously obtained according to a distance from the center of the lens, this data is stored as one-dimensional profile data, and for an image signal obtained by photographing, shading correction is made based on the one-dimensional profile data. In the method of detecting fluorescence, the processing condition is, for example, that a reference sample distributing a fluorescent dye evenly is irradiated with exciting light through an exciting-light cut filter and a diaphragm of 0.85 at each position of the sample-tray disposing sections, the obtained image signal is stored as flat frame data, and based on this flat frame data, shading correction is carried out. In the digitizing method of detecting the reflected or transmitted light of the illuminating light, the processing condition is, for example, that a reference sample with an even density is irradiated with the illuminating light without an exciting-light cut filter and with a diaphragm of 2.8 at each position of the sample-tray disposing sections, the obtained image signal is stored as flat frame data, and based on this flat frame data, shading correction is carried out. In addition, in the digitizing method, flat frame data are obtained in the cases of detecting the transmitted light and reflected light, respectively and shading correction is carried out based on the corresponding flat frame data.
Note that there are cases where in other image processing such as gradation processing, the processing condition is also changed from photographing method to photographing method.
Here, in the conventional photographing system, the photographing method set in the photographing apparatus by the operator, that is, the disposition of a sample onto a suitably selected sample-tray disposing section and the contents of the operation of switching the exciting-light cut filter and the diaphragm in accordance with a photographing object are manually input to the image processing computer by the operator. With this manual input, the image processing after photographing is appropriately performed.
However, there are cases where the operator inputs erroneous contents when the photographing method set in the photographing apparatus is input to the image processing computer. In such a case, an appropriate result of image processing cannot be obtained and therefore there is a possibility that erroneous judgement will be incurred in the quantitative image analysis or the like.
In addition, inputting the contents of the photographing method set in the photographing apparatus one by one to the image processing computer is troublesome, so improvements are desired.
The present invention has been made in view of the aforementioned circumstances. Accordingly, it is an object of the present invention to provide a photographing system that simplifies a switch of image processing to be made by an image processing computer in accordance with a photographing method set in a photographing apparatus by an operator.
The photographing system of the present invention transmits a photographing method set in the photographing apparatus by an operation, that is, the inserted or removed state of an exciting-light cut filter, the diaphragmed state of a variable diaphragm, and a sample-tray disposing section having a sample tray thereon to an image processing computer, thereby automatically determining a condition for image processing to be performed by the image processing computer.
That is, the photographing system of the present invention comprises a photographing apparatus including: (1) a lens movable in an optical axis direction; (2) a plurality of sample-tray disposing sections on which a sample tray placing a predetermined sample thereon is selectively disposed, the sample-tray disposing sections each having a different distance from the lens in the optical axis direction; (3) sample-tray disposing section detection means for detecting one sample-tray disposing section of the plurality of sample-tray disposing sections on which the sample tray was disposed; (4) a light source provided so that it can switch emission and non-emission of exciting light or illuminating light with respect to the predetermined sample on the sample tray disposed on the detected sample-tray disposing section; (5) photoelectric reading means for photoelectrically reading out an image of the predetermined sample, formed on its light-receiving surface by the lens (6) lens movement means for moving the lens in the optical axis direction in accordance with the one sample-tray disposing section detected by the sample-tray disposing section detection means such that the image of the predetermined sample is formed onto the light-receiving surface of the photoelectric reading means; (7) an exciting-light cut filter provided between the lens and the photoelectric reading means so that it can be inserted in or removed from an optical path of light constituting the image of the predetermined sample, the filter having bands set so as to transmit florescence emitted from the predetermined sample and prevent passage of the exciting light; (8) a variable diaphragm provided between the lens and the photoelectric reading means and in proximity to the lens; and (9) a black box shield from light, the components (1) to (8) being housed inside the black box; and an image processing computer for performing predetermined image processing with respect to an image signal representing the image of the predetermined sample read out by the photoelectric reading means. The photographing system further comprises: filter detection means for detecting an inserted or removed state of the exciting-light cut filter; diaphragm detection means for detecting a diaphragmed state of the variable diaphragm; and image processing condition determination means for determining a condition for the predetermined image processing to be performed by the image processing computer with respect to the image signal read out by the photoelectric reading means, in accordance with the inserted or removed state of the filter detected by the filter detection means, the diaphragmed state of the variable diaphragm detected by the diaphragm detection means; and the one sample-tray disposing section detected by the sample-tray disposing section detection means.
The aforementioned light source is capable of selectively emitting exciting light and illuminating light and being switched to three emission and non-emission modes: exciting light emission and illuminating light non-emission, exciting light non-emission and illuminating light emission, and exciting light non-emission and illuminating light non-emission. Note that an exciting light source for emitting only exciting light and an illuminating light source for emitting only illuminating light may be provided separately.
It is preferable that the aforementioned photoelectric reading means employ an interline type CCD equipped with a cooling element, capable of having a wide dynamic range which can detect feeble chemiluminescence and fluorescence with good linearity and also taking out a pseudo-dynamic picture by reiteratively performing photoelectric reading in a short time period.
In the case of a sample (fluorescence detecting sample) distributing specific organism-originated materials labeled with a fluorescent dye, the fluorescence that is emitted from the sample is intended to mean fluorescence which the fluorescent dye labeling the organism-originated materials emits when excited with exciting light. In the case of a sample (chemiluminescence detecting sample) distributing organism-originated materials such as protein that reacts to a predetermined luminescent chemical material or the case of a manuscript such as film, and a photograph, for digitization, the sample or the manuscript emits no fluorescence.
In the case of the aforementioned fluorescence detecting sample, the image of the sample, which is formed onto the light-receiving surface of the photoelectric reading means, is intended to mean the distributed images of specific organism-originated materials labeled with a fluorescent dye. In the case of the chemiluminescence detecting sample, the image of the sample is intended to mean the distributed images of organism-originated materials that react to a predetermined luminescent chemical material. In the case of a translucent manuscript such as film, the image of the sample is intended to mean a reflected image of the manuscript, and in the case of a reflecting manuscript such as a photograph, the image of the sample is intended to mean a reflected image thereof. Note that when, in a focus mode to be described later, an image signal is output as a video signal, the image of the sample is intended to mean a reflected image of the sample reflected by external light or light emitted from a light source.
The aforementioned lens movement means is constituted by a focus ring provided in a lens, etc. and a motor for rotating this focus ring and can employ various means known in the prior art.
The aforementioned variable diaphragm may be switched simply between an open state and a diaphragmed state or switched in stages therebetween.
The aforementioned image processing computer does not need to be a dedicated machine for image processing but may be general-purpose personal computers, workstations, etc. having enhanced calculation processing performance. The image processing to be performed by the image processing computer includes, for example, shading correction processing, flat frame correction processing, etc. and includes at least image processing having a difference in a processing condition and a difference in processing contents in accordance with the kind of sample, i.e., the kind of photographing method.
The specific difference in the image processing condition is as follows: When a photographing method detects chemiluminescence, the processing condition is, for example, that lens brightness data is previously obtained according to a distance from the center of the lens, this data is stored as one-dimensional profile data, and for an image signal obtained by photographing, shading correction is carried out based on the one-dimensional profile data. In the method of detecting fluorescence, the processing condition is, for example, that a reference sample distributing a fluorescent dye evenly is irradiated with exciting light through an exciting-light cut filter and a diaphragm of 0.85 at each position of the sample-tray disposing sections, the obtained image signal is stored as flat frame data, and based on this flat frame data, shading correction is carried out. In the digitizing method of detecting the reflected or transmitted light of the illuminating light, the processing condition is, for example, that a reference sample with an even density is irradiated with the illuminating without an exciting-light cut filter and with a diaphragm of 2.8 at each position of the sample-tray disposing sections, the obtained image signal is stored as flat frame data, and based on this flat frame data, shading correction is carried out. These are differences in the processing condition. In addition, in the digitizing method, flat frame data are obtained in the cases of detecting the transmitted light and the reflected light, respectively and shading correction is carried out based on the corresponding flat frame data, so the processing conditions also differ from each other.
The determination of the condition of the image processing to be performed by the image processing computer in accordance with the inserted or removed state of the exciting-light cut filter, the diaphragmed state of the variable diaphragm, and the position of the sample-tray disposing section having the sample tray thereon is performed by the following specific operation.
First, when the exciting-light cut filter is in the optical path, it is confirmed that the photographing object is a sample of detecting fluorescence emitted therefrom by emission of exciting light, because the exciting-light cut filter is used in the fluorescence detecting sample. When, on the other hand, the exciting-light cut filter is removed out of the optical path, it is confirmed that the photographing object is either a chemiluminescence detecting sample or a digitizing sample. Next, in the open state of the variable diaphragm, it is confirmed that the detecting object is fluorescence or chemiluminescence whose intensity is feeble, because the diaphragmed state of the variable diaphragm limits the quantity of light that is incident on the photoelectric reading means. In an appropriately diaphragmed state, it is confirmed that the detecting object is light from a manuscript for digitization.
Thus, a photographing method (kind of detecting object) can be specified by the inserted or removed state of the exciting-light cut filter and the diaphragmed state of the variable diaphragm, and an appropriate condition for image processing, which differs from object to object being detected, can be determined.
Furthermore, using the result of the detection of the sample-tray disposing section having the sample tray placed thereon, a processing condition for shading correction processing, which differs from sample-tray disposing section to sample-tray disposing section, can be determined.
In a preferred form of the present invention, the photographing system further comprises interrelating means for interrelating switching of the emission and non-emission of the exciting light, which is performed by the light source, with the inserted or removed state of the exciting-light cut filter so that the exciting light is emitted when the exciting-light cut filter is in the optical path and is not emitted when the exciting-light cut filter is out of the optical path. The reason for this is that the operational labor of the operator can be further reduced, if switching between the emission and non-emission of the exciting light is interlocked with switching between the inserted state and the removed state of the exciting-light cut filter, because the exciting-light cut filter is used only in the case of a fluorescent detecting sample.
Note that when the exciting-light cut filter is out of the optical path, exciting light is not emitted from the light source. However, when the variable diaphragm is in the diaphragmed state, the sample is a digitizing sample (manuscript). For this reason, interrelating means may further be provided so that the light source emits illuminating light. However, because the digitizing sample includes a translucent manuscript and a reflecting manuscript, a method of illumination differs between these manuscripts. Therefore, in addition to emitting illuminating light in interrelation with the exciting-light cut filter and the variable diaphragm, there is a need to switch the direction of illumination of the illuminating light. This switching depends upon an operation of the operator. In the case where, for an image signal obtained by digitization, a condition for image processing to be performed by the image processing computer differs according to whether the manuscript is a translucent manuscript or a reflecting manuscript, illumination-switching detection means for detecting switching of the illumination direction of the illuminating light may further be provided, and based on the result of detection from the illumination-switching detection means, the image processing condition determination means may determine an image processing condition corresponding to the kind of digitizing manuscript.
In another preferred form of the present invention, the photographing system further comprises door detection means for detecting a closed or open state of a door formed in the black box and a light source controller for switching on the light source independently of the inserted or removed state of the exciting-light cut filter when the open state of the door is detected by the door detection means. When the door of the black box is open, an image is no longer read out but a preparatory operation for reading, such as insertion or removal of the sample tray, or an operation after reading is performed. Therefore, by illuminating the interior of the black box in interrelation with the open state of the door, labor for the operator to switch on and off the light source can be omitted.
In still another preferred form of the present invention, the photographing system further comprises a camera controller for controlling the photoelectric reading means so that photoelectric reading to be performed by the photoelectric reading means is switched to reading, which is performed reiteratively in a shorter time period than reading for the predetermined image processing, for outputting the image signal as a video signal. By displaying the image of the sample, disposed on the sample-tray disposing section within the black box, on a monitor or the like, a dynamic image can be viewed in approximately real time. It is useful in performing fine adjustments to the lens position (focusing adjustments) in accordance with the thickness of a sample. Note that such a mode of outputting an image signal reiteratively in a short time period will hereinafter be referred to as a focus mode. Also, in the photographing system with both the light source controller and the camera controller described above, there is no need to provide the door detection means in each controller separately and a single door detection means will suffice if it can output door detection signals to both controllers, respectively.
According to the photographing system of the present invention, the photographing method set in the photographing apparatus by the operator, that is, the inserted or removed state of the exciting-light cut filter, the diaphragmed state of the variable diaphragm, and the sample-tray disposing section having a tray placed thereon are detected by the filter detection sensor, the diaphragm detection sensor, and the sample-tray disposing section detection means, respectively. Based on these results of detection, the image processing condition determination means of the image processing computer recognizes the photographing method and determines an image processing condition for performing optimal image processing for each of the photographing methods. For this reason, there is no need to input one by one the contents of the photographing method set in the photographing apparatus by the operator to the image processing computer. Thus, erroneous input and labor of input with respect to the image processing computer can be omitted.